The present invention relates to a method of digital data transmission and/or recording and playback wherein the data are converted in sections to digital signals whose word length is a function of the information density of the data sections.
In the transmission and/or recording and playback of signals, the information density is often subject to fluctuations over time This may apply to untreated signals as well as to those treated in a source coder in order to reduce irrelevance and redundancy. Configuration of the transmission path or record carrier, as the case may be, for the maximum information density is complicated and uneconomical. If the transmission and recording capacity is limited to an average information density by way of time compression and subsequent expansion, i.e. with different word lengths for the data sections as a function of the information density, the problem arises of recognizing the different length data sections after transmission or recording. This recognition becomes even more difficult if interference removes the recognition criteria. It may then happen that even after the interference has gone away, it is no longer possible to recognize the subsequent data sections correctly.